public inbox for linux-arm-kernel@lists.infradead.org
 help / color / mirror / Atom feed
From: "Kevin Mehall" <km@kevinmehall.net>
To: "Mark Brown" <broonie@kernel.org>,
	"Chen-Yu Tsai" <wens@kernel.org>,
	"Jernej Skrabec" <jernej.skrabec@gmail.com>,
	"Samuel Holland" <samuel@sholland.org>,
	"Mirko Vogt" <mirko-dev|linux@nanl.de>,
	"Ralf Schlatterbeck" <rsc@runtux.com>,
	linux-spi@vger.kernel.org, linux-arm-kernel@lists.infradead.org,
	linux-sunxi@lists.linux.dev, linux-kernel@vger.kernel.org
Subject: Re: [PATCH v2 1/2] spi: sun6i: Honor CS setup delay on the first transfer with native CS
Date: Thu, 23 Apr 2026 12:40:34 -0600	[thread overview]
Message-ID: <53c2d366-2d76-4a6d-a72b-99544026ee27@app.fastmail.com> (raw)
In-Reply-To: <20260423174001.2797797-2-km@kevinmehall.net>

I realized this is incorrect. With a GPIO chip select, sun6i_spi_set_cs() is not called,
thus CS_MANUAL would not be set, and the hardware would then automatically
assert native CS 0 during the transfer. My testing was with native CS 1 and a second GPIO chip select,
so I didn't see this because native CS 0 is not used on the Orange Pi Zero 3.

Therefore, I think the best place to set CS_MANUAL is in sun6i_spi_prepare_message
as I had in my original patch [1], unless you think it should be duplicated in both places
or have a better suggestion of where to set it. sun6i_spi_prepare_message() is still called
before set_cs(), so it still fixes the skipped delay.

[1]: https://lore.kernel.org/linux-spi/20260420164755.1131645-1-km@kevinmehall.net/


  reply	other threads:[~2026-04-23 18:43 UTC|newest]

Thread overview: 5+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2026-04-23 17:39 [PATCH v2 0/2] spi: sun6i: Fix chip select handling around autosuspend Kevin Mehall
2026-04-23 17:40 ` [PATCH v2 1/2] spi: sun6i: Honor CS setup delay on the first transfer with native CS Kevin Mehall
2026-04-23 18:40   ` Kevin Mehall [this message]
2026-04-23 18:50     ` Mark Brown
2026-04-23 17:40 ` [PATCH v2 2/2] spi: sun6i: Set SPI mode in prepare_message Kevin Mehall

Reply instructions:

You may reply publicly to this message via plain-text email
using any one of the following methods:

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

  Avoid top-posting and favor interleaved quoting:
  https://en.wikipedia.org/wiki/Posting_style#Interleaved_style

* Reply using the --to, --cc, and --in-reply-to
  switches of git-send-email(1):

  git send-email \
    --in-reply-to=53c2d366-2d76-4a6d-a72b-99544026ee27@app.fastmail.com \
    --to=km@kevinmehall.net \
    --cc=broonie@kernel.org \
    --cc=jernej.skrabec@gmail.com \
    --cc=linux-arm-kernel@lists.infradead.org \
    --cc=linux-kernel@vger.kernel.org \
    --cc=linux-spi@vger.kernel.org \
    --cc=linux-sunxi@lists.linux.dev \
    --cc=mirko-dev|linux@nanl.de \
    --cc=rsc@runtux.com \
    --cc=samuel@sholland.org \
    --cc=wens@kernel.org \
    /path/to/YOUR_REPLY

  https://kernel.org/pub/software/scm/git/docs/git-send-email.html

* If your mail client supports setting the In-Reply-To header
  via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox